1. Field of the Invention
The present invention relates to agricultural harvesters, and, more particularly, to header assemblies for agricultural harvesters.
2. Description of the Related Art
Combines are used to harvest agricultural crops such as corn, soybeans, wheat and other grain crops. As the combine is driven through a crop field, the combine cuts the crop, separates the desired crop from the undesired waste, stores the crop, and discards the waste.
In a typical combine, a header is mounted at the front of the combine to gather the crop and feed the crop into the combine for processing. In a continuous process as the combine is driven through the field, the crop material is collected by the header, deposited into a feeder housing and transported upwardly into the combine by a feed elevator located within the feeder housing. The crop material then passes through a threshing and separating mechanism in which the crop material is impacted and/or rubbed, thereby causing the grain to separate from the stalk material. In a rotary combine, the threshing and separating mechanism includes a rotor, a threshing concave, a rotor cage and a separating grate; however, many types of combines are known that perform similar functions using different mechanisms. The stalk material that is separated from the grain is commonly referred to as material other than grain (MOG).
After passing through the threshing and separating assembly, the grain and MOG are deposited onto a grain cleaning system to separate the grain from the MOG. The grain cleaning system typically includes a plurality of adjustable, reciprocating cleaning sieves, often referred to as a chaffer sieve and a shoe sieve. To further separate the grain from the MOG, a cleaning fan or blower is positioned to blow air up through the cleaning sieves. The flow of air tends to blow the MOG, which is typically lighter than grain, out the back of the combine. Grain, which typically is heavier than MOG, is allowed to drop through the openings in the sieves.
The clean grain that falls through the cleaning sieves is deposited on a collection panel positioned beneath the cleaning sieves. The collection panel is angled so as to permit the grain to flow, under the influence of gravity, into an auger trough positioned along the lowermost edge of the collection panel. The grain collected in the auger trough is then moved by an auger towards the side of the combine where it is raised by a grain elevator and deposited into a storage tank or grain tank.
The header is designed to cut a swath in the crop of substantial width, and to convey the cut crop material into the feeder housing, typically the feeder housing being substantially narrower than the swath width cut by the header. An infeed assembly can be included in the header to direct the cut crop material from the outer portions of the header into a middle area of the header for movement into the feeder housing for transport to the threshing and separating mechanism. It is known to use opposed feed augers having helically oriented flights to convey the cut crop material laterally inward toward the center of the header. Center support structures are provided for the conveying augers. The opposed feed augers operating with necessary support structures and the associated part stack up create a center zone without positive crop material conveyance by the augers. While the conveyed crop material will urge other crop material through the zone and into the feeder housing, under some conditions, crop material can stagnate in a re-circling pattern within the center zone, thereby hindering movement of the crop material into the feeder housing. However, the presence of supporting structure makes it difficult to install mechanism to positively move the crop material through the center zone and into the feeder housing.
What is needed in the art is an infeed assembly that can overcome some of the previously described disadvantages of the prior art.